1. Field of the Invention
The present invention relates to an information processing apparatus, such as, for example, a personal computer and peripheral devices thereof, and to an information processing system formed of these information processing apparatuses.
2. Description of the Related Art
In recent years, as a recording and playback apparatus, a CD-R/RW (Recordable/Rewritable) drive unit which performs recording and playback of data in accordance with a data recordable and playable disk, such as a recordable CD-R or a rewritable CD-RW, has become popular.
Although such a CD-R/RW drive unit, on a standalone basis, can play back a disk recorded independently in, for example, a CD-DA (Digital Audio) format, typically, the CD-R/RW drive unit is used as a peripheral device for a personal computer as a result of being connected to the personal computer via a data interface, such as, for example, USB, SCSI, etc.
As use forms thereof, as has already been well known, first, application software for controlling the CD-R/RW drive unit is installed on a personal computer. A user starts this application and performs operations on the personal computer, thereby making it possible to read data from a disk loaded into the CD-R/RW drive unit connected to this personal computer or to write data stored in the personal computer.
Also, in recent years, what is commonly called a notebook-type personal computer has become widely used. The notebook-type personal computer is smaller and lighter than, for example, what is commonly called a desktop-type personal computer, and furthermore, can be powered by a battery, in addition to an AC power supply, such as a charger. As a result, the notebook-type personal computer is more portable, and it is possible for the user to use the personal computer, for example, while on the move.
Against a background such as that described above, peripheral devices, such as, for example, CD-R/RW drive units described above, which are made smaller and lighter in order to be portable are also becoming popular. So, in order for higher portability to be obtained, a CD-R/RW drive unit to which power can be supplied by a charger, a dry battery, etc. has been proposed.
It is assumed that user data transferred from the personal computer side is being recorded into a CD-R/RW drive unit which is driven by, for example, a battery. At this time, if the remaining battery level of the CD-R/RW drive unit becomes zero, and the CD-R/RW drive unit stops operation, at this point in time, it is not possible for the personal computer side to complete the recording of a cluster of data which was being written at that time. More specifically, it is not possible to perform, for example, a closing process of what is commonly called a session. In such a case, since, on the disk, a file system for the data which has been actually written on the disk thus far does not exist, the data written up to that time is treated as not being present on the disk. That is, the user data which should have been written on the disk would be lost. In particular, for a rewritable CD-RW, depending on the recording method thereof, unless the file system is correctly written in the above-described manner, there may occur a case in which even data packets which were recorded previously is also not recognized and is lost.
In the manner described above, in a battery-driven CD-R/RW drive unit, when the remaining battery level becomes zero, the user data which has been written on the disk up to the present time is lost and the disk cannot be used. Therefore, there is a demand for measures for preventing this problem.